erosita mirror calibration:

Transcription

1 erosita mirror calibration: First measurements and future concept PANTER instrument chamber set-up for XMM mirror calibration: 12 m length, 3.5 m diameter: 8m to focal plane instrumentation now: f = 1.6 m; cameras = PSPC, EPIC-pn, TRoPIC IACHEC 2008, Schloss Ringberg, May

2 erosita product tree of telescope FM telescope = 7 modules with 54 shells each + 7 cameras telescope infrastructure optical bench cover and mechanism thermal control system baffle mirror system mirrors structure cameras camera housing CCD module electronics box electronics and software IACHEC 2008, Schloss Ringberg, May

3 erosita optics at PANTER: test objects telescope = 7 modules with 54 shells each + 7 cameras single shell 44/3 (ABRIXAS mandrel),... single shell 46/1, 46/2, 46/8 (ABRIXAS mandrel) single shell 27/4 (MLT mandrel),... single shell 1 (MLT mandrel): to be installed tomorrow single shell 2 (Zeiss mandrel): to be installed tomorrow DM (QM): shells FM1 FM2,..., FM7 (incl. cameras) end-to-end test IACHEC 2008, Schloss Ringberg, May

4 erosita optics at PANTER: test subjects (on-axis) delivery, visual inspection, installation optical alignment (laser) X-ray alignment (Burkert test) point spread function (HEW, W90) at various energies: large-scale (PSPC, e.g. scattering, micro-roughness) small-scale (TRoPIC): pixel scan : (3.75 µm step) raster over 1 pixel to avoid split bias re-shift coordinates and merge exposures sub-pixel resolution via split event statistics single reflections: parabola entrance (mounting at spider), hyperbola entrance (close to mid-plane) out-of-focus rings (position, width, pseudo-hartmann test) effective area at various energies (full illumination, Glücksrad ) gold edge, off-axis behaviour, contamination control,... IACHEC 2008, Schloss Ringberg, May

5 erosita: mechanical interface (GSE) Mounted onto rotate-tilt-stage for X-ray alignment and dedicated off-axis exposures IACHEC 2008, Schloss Ringberg, May

6 Set-up at PANTER Shell and finger spider before mounting of entrance aperture In the back: PSPC (right), TRoPIC (middle), EPIC-pn (partially covered) IACHEC 2008, Schloss Ringberg, May

7 Tube exit In the back: exit of 123 m tube, with various aperture stops Distance source - mirror midplane: 130 m: maximum (full) divergence angle 9.5 IACHEC 2008, Schloss Ringberg, May

8 ero-27/4: alignment (PSPC) out-of-focus off-axis single reflections (hyperbola, parabola) IACHEC 2008, Schloss Ringberg, May

9 ero-27/4: alignment (PSPC): on-axis (combined image) combined image: symmetric IACHEC 2008, Schloss Ringberg, May

10 ero-27/4: out-of-focus (PSPC): on-axis 16 fingers of spider, zoomed image IACHEC 2008, Schloss Ringberg, May

11 ero-27/4 PSF: TRoPIC: HEW = 25 (22.5) arcsec (Al-K) IACHEC 2008, Schloss Ringberg, May

12 ero-46/8 PSF: TRoPIC: HEW = 17 (14.7) arcsec (Al-K) IACHEC 2008, Schloss Ringberg, May

13 ero-46/8: towards sub-pixel resolution randomize events within split area (i.e. where doubles, tripels etc. are generated) instead of within full pixel (like in XMM-SAS), this improves spatial resolution: HEW 17 arcsec 14.7 arcsec IACHEC 2008, Schloss Ringberg, May

14 ero-46/2: single reflections (PSPC) outer ring: hyperbola close to mid-plane inner ring: parabola close to entrance at higher energies: outer ring disappears due to large incidence angles IACHEC 2008, Schloss Ringberg, May

15 ero-46/8: single reflections (TRoPIC mosaic) single reflection rings, out-of-time events, pile-up in PSF core IACHEC 2008, Schloss Ringberg, May

16 Out-of-focus rings: position and width IACHEC 2008, Schloss Ringberg, May

17 Out-of-focus ring geometry: position and width Shell mid-plane radius exit radius distance ring center ring width # r m [mm] r u [mm] s [mm] r c [mm] w [mm] focal plane instrumentation at PANTER: along optical axis: ±250 mm highest spatial resolution: TRoPIC: FOV 19.2 mm squared out-of-focus rings allow spatial location of features IACHEC 2008, Schloss Ringberg, May

18 ero-46/2: out-of-focus rings + single reflections (PSPC) intrafocal: parabola and hyperbola single reflections, double-reflection ring extrafocal: hyperbola and parabola and single reflections, double-reflection ring cross-sections of double-reflection ring, if sufficient spatial resolution: IACHEC 2008, Schloss Ringberg, May

19 ero-46/2: out-of-focus rings (TRoPIC): data + theory IACHEC 2008, Schloss Ringberg, May

20 ero-46/2: -250, +200, -40, +40, -20, +20 mm out-of-focus mirrored rings from intra-focal to extra-focal IACHEC 2008, Schloss Ringberg, May

21 ero-46/2: Pseudo-Hartmann test: in-focus prediction 0.2 2d positions: 2mm intrafocal 0.2 2d positions: 1mm intrafocal 0.2 2d positions: focus d positions: 0.5mm extrafocal d positions: 1mm extrafocal d positions: 2mm extrafocal interpolation of -250mm intrafocal and +200mm extrafocal images to focus position: -2mm, -1mm intrafocal, 0mm, +0.5mm, +1mm, +2mm extrafocal IACHEC 2008, Schloss Ringberg, May

22 ero-27/4: effective areas IACHEC 2008, Schloss Ringberg, May

23 erosita: effective areas via Glücksrad put open mirror aperture parallel to incident beam any aperture from 0 to 45 (2 sectors) sum of sectors gives parallel beam effective area IACHEC 2008, Schloss Ringberg, May

24 erosita flight models FM1: according to schedule will be delivered prior to first camera FM FM1: calibrate extensively with TRoPIC FM1: mount X-ray baffle FM1: double crystal monochromator for gold edge (2.1 3 kev) FM1: calibrate afterwards with corresponding camera FM1 focal length, determine effects of camera pile-up, stray-light,... FM2,..., FM7 (incl. cameras) end-to-end test: only 1 3 modules in beam IACHEC 2008, Schloss Ringberg, May

25 erosita in-orbit calibration with cosmic sources: comments bright sources may saturate telemetry ( disk quota ) (1 event per readout-cycle per camera): these limits depend on other payload and calibration agreements standard sources: N132D, Mkn421, PKS2155, 1E0102, Crab, Vela: XMM: cts/s background in LEO: fluorescent O-K line (532 ev) from scattered solar X-rays IACHEC 2008, Schloss Ringberg, May

26 erosita in-orbit calibration with cosmic sources: strategy? observe source only with one (or more) camera active at the same time, and use other cameras with closed filter position give more (all?) telemetry to erosita during calibration observations split telemetry for S-X-G cross-calibration observations calibration observations in survey mode surveys could be interrupted for pointed calibration observations (every 6 months for e.g. 2 days, dependent on target visibility) IACHEC 2008, Schloss Ringberg, May

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